A 34-year-old woman with a family history of pregnancy-associated thrombotic disease developed pre-eclampsia in her 8th month of pregnancy. A severe haemolytic-uraemic syndrome (HUS) developed within 24 h after spontaneous delivery. Because the plasma antithrombin-III (AT-III) was only 15% of the normal concentration, an AT-III concentrate was given intravenously. When the normal level of plasma AT-III was reached, the clinical and biochemical signs of the syndrome disappeared. Renal function and biopsy were normal within 10 days. Because complete recovery is unusual in patients with post partum HUS and no previous reports have described a rapid recovery, the case reported here suggests that infusion of an AT-III concentrate should be tried when plasma AT-III is significantly decreased.